Nitride semiconductor laser device and method of manufacturing the same

Abstract

A nitride semiconductor laser device is formed by growing a group III nitride semiconductor multilayer structure on a substrate. The group III nitride semiconductor multilayer structure has a laser resonator including an n-type semiconductor layer, a p-type semiconductor layer and a light emitting layer held between the n-type semiconductor layer and the p-type semiconductor layer. The laser resonator is arranged to be offset from the center with respect to a device width direction orthogonal to a resonator direction toward one side edge of the device. A wire bonding region having a width of not less than twice the diameter of an electrode wire to be bonded to the device is formed between the laser resonator and the other side edge of the device.

1. A nitride semiconductor laser device formed by growing a group III nitride semiconductor multilayer structure on a substrate, wherein
 the group III nitride semiconductor multilayer structure has a laser resonator including an n-type semiconductor layer, a p-type semiconductor layer and a light emitting layer held between the n-type semiconductor layer and the p-type semiconductor layer, 
 the laser resonator is arranged to be offset from a center with respect to a device width direction orthogonal to a resonator direction toward one side edge of the device, 
 a wire bonding region having a width of not less than twice a diameter of an electrode wire to be bonded to the device is formed between the laser resonator and the other side edge of the device, and 
 a substrate dividing groove trace is formed on a side edge of the device, and a device thickness h of the remaining portion excluding the substrate dividing groove trace and a device width W in the direction orthogonal to the resonator direction satisfy W≧1.4 h. 
 
     
     
       2. The nitride semiconductor laser device according to  claim 1 , wherein
 the laser resonator is offset from the center in the device width direction toward the one side edge of the device by a distance of not less than the diameter of the electrode wire. 
 
     
     
       3. The nitride semiconductor laser device according to  claim 1 , wherein
 the substrate periodically has a region having a first dislocation density and a region having a second dislocation density lower than the first dislocation density on the surface, and 
 the laser resonator is arranged on the region having the second dislocation density. 
 
     
     
       4. The nitride semiconductor laser device according to  claim 1 , wherein
 the substrate not yet divided into each device periodically has a region having a first dislocation density and a region having a second dislocation density lower than the first dislocation density on the surface, 
 the laser resonator is arranged on the region having the second dislocation density, and 
 the region having the first dislocation density is not included in the device. 
 
     
     
       5. The nitride semiconductor laser device according to  claim 1 , wherein
 a metallic pattern for bonding the electrode wire is formed on the center with respect to the device width direction orthogonal to the resonator direction. 
 
     
     
       6. A nitride semiconductor laser device formed by growing a group III nitride semiconductor multilayer structure on a substrate, wherein
 the group Ill nitride semiconductor multilayer structure has a laser resonator including an n-type semiconductor layer, a p-type semiconductor layer and a light emitting layer held between the n-type semiconductor layer and the p-type semiconductor layer, and 
 a substrate dividing groove trace is formed on a side edge of the device, and a device thickness h of the remaining portion excluding the substrate dividing groove trace and a device width W in a direction orthogonal to a resonator direction satisfy W≧1.4 h. 
 
     
     
       7. A method of manufacturing a nitride semiconductor laser device, including the steps of:
 forming a group III nitride semiconductor multilayer structure having a laser resonator including an n-type semiconductor layer, a p-type semiconductor layer and a light emitting layer held between the n-type semiconductor layer and the p-type semiconductor layer on a substrate; and 
 dividing the substrate so that the laser resonator is arranged to be offset from a center with respect to a device width direction orthogonal to a resonator direction toward one side edge of the device, and forming a wire bonding region having a width of not less than twice the diameter of an electrode wire to be bonded to the device between the laser resonator and the other side edge of the device, wherein 
 the step of forming the wire bonding region includes the steps of: 
 forming a substrate dividing groove on the substrate so that a device thickness h of the remaining portion excluding a substrate dividing groove trace and a device width W in the direction orthogonal to the resonator direction satisfy W≧1.4 h; and 
 dividing the substrate along the substrate dividing groove. 
 
     
     
       8. The method of manufacturing a nitride semiconductor laser device according to  claim 7 , wherein
 the step of forming the wire bonding region includes a step of dividing the substrate so that the laser resonator is arranged to be offset from the center in the device width direction toward the one side edge of the device by a distance of not less than the diameter of the electrode wire. 
 
     
     
       9. The method of manufacturing a nitride semiconductor laser device according to  claim 7 , wherein
 the substrate periodically has a region having a first dislocation density and a region having a second dislocation density lower than the first dislocation density on the surface, and 
 the laser resonator is arranged on the region having the second dislocation density. 
 
     
     
       10. The method of manufacturing a nitride semiconductor laser device according to  claim 7 , wherein
 the substrate not yet divided into each device periodically has a region having a first dislocation density and a region having a second dislocation density lower than the first dislocation density on the surface, 
 the laser resonator is arranged on the region having the second dislocation density, and 
 the substrate is so divided as not to include the region having the first dislocation density in the device. 
 
     
     
       11. The method of manufacturing a nitride semiconductor laser device according to  claim 7 , further including a step of forming a metallic pattern for bonding the electrode wire on the center related to the device width direction orthogonal to the resonator direction. 
     
     
       12. A method of manufacturing a nitride semiconductor laser device, including the steps of:
 forming a group Ill nitride semiconductor multilayer structure having a laser resonator including an n-type semiconductor layer, a p-type semiconductor layer and a light emitting layer held between the n-type semiconductor layer and the p-type semiconductor layer on a substrate; 
 forming a substrate dividing groove on the substrate so that a device thickness h of the remaining portion excluding the substrate dividing groove and a device width W in a direction orthogonal to a resonator direction satisfy W≧1.4 h; and 
 dividing the substrate along the substrate dividing groove. 
 
     
     
       13. The method of manufacturing a nitride semiconductor laser device according to  claim 12 , wherein
 the substrate periodically has a region having a first dislocation density and a region having a second dislocation density lower than the first dislocation density on the surface, and the laser resonator is arranged on the region having the second dislocation density. 
 
     
     
       14. The method of manufacturing a nitride semiconductor laser device according to  claim 12 , wherein
 the substrate not yet divided into each device periodically has a region having a first dislocation density and a region having a second dislocation density lower than the first dislocation density on the surface, 
 the laser resonator is arranged on the region having the second dislocation density, and 
 the substrate is so divided as not to include the region having the first dislocation density in the device.